Heat exchanger



J. E. WEIKS HEAT EXCHANGER Filed Dec. 22. 1960 March 2, 1965 INVENTOR.

United States Patent O 3,171,478 HEAT EXCHANGER John E. Weiks, 404 SW. 171st Place, Seattle 66, Wash. Filed Dec. 22, 1960, Ser. No. 77,774 2 Claims. (Cl. 165-143) My invention relates to a heat exchanger of a type disclosed in my prior Patents No. 2,513,124 4and No. 2,577,832 and which is particularly well adapted for use as a marine engine cooler in connection with engines wherein fresh water is circulated in the cooling jacket spaces of the engine and salt or sea water is used for cooling the fresh water.

An object of my invention is to provide a heat exchanger composed of separable units which can be assembled in multiples of two or more units to provide heat exchangers of greater or less capacity as may be required for different engines, the capacity of each heat exchanger depending on the number of units embodied in it.

Another object is to provide a heat exchanger of simple construction which is easy to service and repair and in which any damaged or defective units can be quickly and easily replaced by similar units which are in good working condition.

Another object of my invention is to provide heat exchange units which, to as great an extent as possible, are made up of duplicate parts and in which the units can be assembled in multiples of different numbers to provide heat exchangers of a wide range of different capacities, thereby minimizing initial manufacturing costs and making it possible for dealers who only stock a small number of different parts to build up from those parts heat exchangers of Substantially any capacity they are liable to be called on to furnish.

A further object of my invention is to provide a heat exchanger made up of an assembly of two outside heat exchange units of duplicate construction and any desired number of intermediate heat exchange units all of duplicate construction but of a construction differing somewhat from that of the outside heat exchange units, all of the units in each heat exchanger being communicatively connected so as to provide for a separate circulation of liquids of two dierent temperatures therethrough.

Another object is to provide a multiple unit heat exchanger in which each unit comprises two spaced apart head fittings of generally rectangular cross section connected by two pairs of return flow conduits, each pair of conduits comprising a larger outer conduit having therein a coaxially disposed inner conduit of substantially smaller diameter than the outer conduit, the head blocks of rectangular cross section having fiat outer sides capable of abutting flatly and squarely against each other in forming multiple unit heat exchange assemblies which are rugged and substantial and not easily damaged.

Other objects of my invention will be apparent from the following description taken in connection with the accompanying drawings.

In the drawings FIGURE 1 is a top plan view, with parts broken away, showing a three unit heat exchanger constructed in accordance with my invention.

FIG. 2 is a side elevation of the same looking in the direction of broken line 2-2 of FIG. l.

FIG. 3 is an end view looking in the direction of broken line 3-3 of FIG. 2.

FIG. 4 is a cross sectional view taken substantially on i broken line 4--4 of FIG. 2.

FIG. 5 is a sectional view taken substantially on broken line 5 5 of FIG. 1 showing an inner pipe in elevation and showing a fragment of a diagonal U-shaped end connector member.

3,171,478 Patented Mar. 2, 1965 ICC FIG. 6 is a sectional View taken substantially on broken line 6-6 of FIG. 5, showing inner pipes in plan and showing a fragment of a diagonal U-shaped end connector member in section.

FIG. 7 is a detached plan View of a front return intermediate fitting and fragments of pipes which are connected therewith.

FIG. 8 is a detached edge View of said front return intermediate fitting, the pipes being omitted.

FIG. 9 is a fragmentary sectional view taken substantially on broken line 9 9 of FIG. 2, showing a rear return fitting, two inside pipes being shown in plan.

FIG. l0 is a sectional view, with an inside pipe in elevation, taken substantially on broken line 10-10 of FIG. 9.

Like reference numerals refer to like parts throughout the several views.

The heat exchanger shown in the drawings is made up of three return iiow heat exchange units indicated generally by A, B and C, FIGS. 1, 2, 3 and 4, and all secured together in face to face relation. The twounits A and C are outside units and are of duplicate construction. The unit B is an intermediate unit and differs in construction from the units A and C. Said unit B can be omitted, in which instance a heat exchanger of minimum capacity will be provided by the two outside units A and C. Also more than one intermediate unit B can be used between two outside units A and C to provide a heat exchanger of greater than three unit capacity. All intermediate units B are of duplicate construction and they differ from the outside units A and C, as hereinafter explained. For the purpose of this description the end of the heat exchanger shown at the right in FIGS. l and 2 will be referred to as the head or front end because all of the iiuid conduits are connected with this end. The end shown at the left, FIGS. 1 and 2, is herein referred to as the rear end. Also because the two outside units A and C are of duplicate construction the following description, including reference numerals used, will apply equally well to either of said units.

Each outside heat exchange unit A and C comprises a front terminal casting or fitting 15 and a rear return casting or fitting 15 connected with each other by two spaced apart, parallel larger outer pipes 17 and 18 and two inner pipes 20 and 21. The inner pipes 20 and 21 are of substantially smaller diameter than the outer pipes 17 and 18 and are concentrically disposed within said outer pipes so that an annular liow passageway 14 is provided between each outer pipe and the inner pipe therein. Preferably all of the pipes 17, 18, 20 and 21 are of copper or like non-corrosive material.

Each front terminal fitting 15, FIGS. 4, 5 and 6, has two side by side internal recesses 22 and 23 which have counterbores 24 at their inner ends to receive end portions of the larger pipes 17 and 18. Preferably the pipes 17 and 18 are soldered or brazed in the counterbores 24. The outer ends of the recesses 22 and 23, shown at the right in FIGS. 1, 2, 5 and 6, are intersected by coaxial bores 25 of smaller diameter than said recesses through which the end portions of the smaller pipes 20 and 21 extend. Preferably the pipes 20 and 21 are soldered or brazed in the bores 25. A forwardly directed, tubular, off-center, L-shaped terminal conduit member 26 is formed on the outer side of each front terminal fitting 15 and communicates with the internal recess 23 thereof. The other internal recess 22 of each fitting 15 communi- Cates with a diagonal passageway 27, FIG. 4, which terminates at the innermost side or face of the fitting, that is, the side opposite the L-shaped conduit 26 and substantially mid-way between the two ends of said fitting.

The foremost side of each front terminal fitting 15 has a medially positioned transverse boss 30 provided with a Each rear' return fitting 16, FIGS. l and 2 left, and

FIGS. 9 and l0, has two side by side internal recesses 32 and 33 each provided with a counterbore 34 at one end to receive the end portions of the larger outer pipes 17 and 18 and each interseetedV by a bore'35' of smaller diameter Vat the other endV through which the smaller inner pipes 20 and21 pass to the exteriorof the fitting lo. The two internal recesses 32` and 33 of each return tting 16 are cornnrunicatively connected with each other by a cross passageway 36, FIG. 9, so that liquid'can pass freely between the two larger outer pipes 17 and 18.

VThe outer end of each rear return fitting 16 is externally provided with a transverse upright rib or boss 37 similar to the previously described boss and having therein a perfor-ation 4t) to receive a bolt 28 for assembly n purposes.

The end portions of .the two smaller inner pipes Ztl and 21 of each unit A and C protrude a substantial distance to the left, FIGS.; l, 2, 9 IaridlO, from the fittings 16 and are communicatively connected with each other by a U-s'haped return conduit member 42.

Each intermediate heat exchange unit B includes one' of the rear return fittings 16. Also each intermediate unit B includes a front fitting 43, FIGS. 2, 7 andV 8,'constructed4 differently from the fittings 15 and 16. Two outer pipesl 44 and 45, of larger diameter, and two concentrical-ly positioned inner pipes 46 and 47 of smaller diameter than said outer pipes extend between the front fitting 43 and the rear fitting 16 of the Yin-termediate unit.

B. The smaller pipes 46 `and 47y of each intermediate unit B are communicatively connected withV each other ternal recess 50 of the fitting 43 communicates with a diagonal passageway 55, FIG. 4, which'terminates in one face of' said fitting 43. The internal recess 51 of 'said tting 43 communicates with .a second diagonal passageway 54 which extends to and terminates in the opposite face of said fitting 43. Numerals 56 indicate diag-` onally positioned U-shaped tubular return conduits which cornmunicatively connect smaller pipes ofadjacent units' A, B and C. A Y Y By way of illustration I have shown two outside heat exchangeY units A and C and one intermediate heat exchangeunit B assembled face to face' and secured together by bolts 28v to forrn a heat exchanger of a` predetermined heat exchange capacity. It will be understood that a heat .exchanger of lesser heat exchange capacity can be provided by omitting intermediaterunit B and using only the two outside units A and C. Also that a heat exchanger of greater heat exchange capacity can be provided by usingA more than one intermedia-te unit B in the assembly. The flow capacity will be approximately constant irrespectiveV of the number of heat exchange units used in lthe assembly. Obviously two or more of these heat exchangers can be connected in parallel to secure a greater iow capacity, if desired. Y

When two or more of the units A, B and C are assembled in the manner shown the outlet openings of the sevyeral diagonal passageways 27, 54 andf55 register, as shown in FIG. 4, and gaskets 57, which preferably are conventionalY O-rings, are used as liquid seal members in shallow counterbores 5S., FIGS. 7 and 8, aroundthe register-A ing openings of said ,passageways' and between the abut- .ting faces of ,the ,terminal fittings 15 and front fitting 43.

All'brazed and soldered joints are arranged in such a manner that lno instance ofle-akage of said joints can cause a mixing of the two heat exchange liquids. This safeguards the lmotor in connection with which this heat exchanger is used.

VIn the use of this heat exchangeras a marine engine cooler preferably the two protruding ends of theV smaller pipes 21 ofthe outside units A andC are connected with suitable conduitsf'l", a fragment of one conduit 61 being shownin FIG. 6, by which cold liquid, such as sea water can be Vcirculated throughthe smallerpipes of the exchanger. The two VL-shaped terminal conduit' members 26 of the outside units A and C are connected with suit- -able conduits 62, la fragment of one conduit 62 being lshown in FIG. 2, which lead to the water jacket spaces of a motor. Independent pumps are used to circulate the cooling water or liquid and the liquid to be cooled'. Cool sea water entering a smaller pipe of one ofthe outside units A or C will flow back and forth throughout the lengthI of lall of said smaller pipes and be discharged from a smaller' pipe of the other unit. At the same time heated liquid,- such as fresh water, from the water jacket spaces of a motor can be causedV to flow throughout the length of all of the largerpipes in the annular spaces 14. In so doing it will give up heat to' the cooler water in the smaller pipes and will be returned `in a cooled condition to` the jacket spaces of the motor. Obviously thecirculation of the two liquids can be a counterflow circulation if desired. Also, because the hot liquid is circulating in thelarger outer pipes'and theselarger outer pipes are exposed to the air some heat from the hot liquid will be given up to the surrounding air and the Vcooling efficiency of thel device will be increased.

All of the pipesY in each heat exchange unit are soldered orbrazed to the Vterminal nttings. Liquid vof one temperature is circulated within the smaller pipes and' liquid of a different temperature is circulated within the annular rpassageway/s. 14=between the smaller and larger pipes.

This can. result in unequal longitudinal expansion and contraction of the smaller and larger pipes. To minimize undesirable effects of such unequal expansion and contraction VI provide in each larger pipe one or more an-V nular corrugations 60 which will permit enough longil tudinal expansion and contraction of these larger pipes to obviate any danger of damage due to unequal expansion and contraction.

The foregoing description and accompanying drawings clearly disclose a preferred embodiment of my invention but it will be understood that this disclosure is merely illustrative and that changes in the invention maybe made within the scope of the following claims.

I claim:

l. In a heat exchanger, a plurality of assembled heat exchange units each comprising two spaced apart head blocks; two transversely spacedapart parallel sets of pipes connected with and extending betweeneach pair of head blocks, each set of pipescomprising a larger outer pipe and a. smaller inner pipe coaxial within the outer pipe providing a flow passageway within 'the smaller pipes for liquid of one temperature and an annular flow passageway between the smaller and larger pipes for liquid of another temperature, each head block having larger bores' receiving the pipes of larger diameter and smaller bores through which the pipes of smaller diameter extend through and beyond the head blocks; a transverse passageway in each head bl-ock at one end of the assembled units connecting the larger bores of the head block and the annular flow passageways of the two sets of pipes of the unit with each other; a transverse Urshaped conduit at said one end of an adjacent unit; other U-shaped conduits at said other end `of the assembled units connecting diagonally opposite smaller pipes of adjacent units; and inlet 4and outlet means for liquid of different temperatures communicatively connected respectively with smaller pipes and with annular ow passageways of the head blocks at said other end of said assembled units.

2. A heat exchanger comprising a plurality of return ow heat exchange units capable of being assembled and secured together in selected numbers of at least two units in an assembly to provide heat exchangers of different heat exchange capacities depending on the number of heat exchange units used in the assembly, each unit comprising a front head fitting and a rear head tting spaced from each other; two transversely spaced apart parallel pairs of coaxial pipes extending between the two spaced ,apart iittings of each unit, the two pipes of each pair being of different diameters providing an annular flow passageway between the two pipes of each pair and another flow passageway through the pipes of smaller diameter, the pipes of smaller diameter extending entirely through and protruding from the two head fittings, the rear head tting of each unit being provided with return flow passageways communicatively connecting the annular ilow passageways of the two sets of pipes of the unit; U-shaped conduit members communicatively connecting the end portions of the two pipes of smaller diameter which protrude from the rear head fitting of each unit; means securing a plurality of said units together in forming a complete heat exchanger; other U-shaped c-onduit members at the forward end of the assembled units positioned diagonally and connecting smaller pipes of adjacent units; at least one diagonal passageway in each front head tting communicatively connected with the annular flow passageway of one set of pipes of said unit and adapted to register with a corresponding diagonal passageway of an adjacent unit, whereby fluid in the annular flow passageway of one unit is .transferred to the diagonally opposite annular flow passageway of an adjacent unit; inlet and outlet conduit means for one Huid connected with one smaller pipe which protrudes from the head tting of each unit; and uid inlet and outlet conduits for another fluid connected with the front head fitting of each unit and communicating with the annular liquid flow conduit of one set of pipes of the unit.

References Cited in the file of this patent UNITED STATES PATENTS 1,821,934 Feldmeier Sept. 8, 1931 1,845,256 Feldmeier et al Feb. 16, 1932 1,850,678 Landvoight Mar. 22, 1932 2,236,470 De .Tonge Mar. 25, 1941 FOREIGN PATENTS 687,727 Germany Feb. 5, 1940 

1. IN A HEAT EXCHANGER, A PLURALITY OF ASSEMBLED HEAT EXCHANGE UNITS EACH COMPRISING TWO SPACED APART HEAD BLOCKS; TWO TRANSVERSELY SPACED APART PARALLEL SETS OF PIPES CONNECTED WITH AND EXTENDING BETWEEN EACH PAIR OF HEAD BLOCKS, EACH SET OF PIPES COMPRISING A LARGER OUTER PIPE AND A SMALLER INNER PIPE COAXIAL WITH THE OUTER PIPE PROVIDING A FLOW PASSAGEWAY WITHIN THE SMALLER PIPES FOR LIQUID OF ONE TEMPERATURE AND AN ANNULAR FLOW PASSAGEWAY BETWEEN THE SMALLER AND LARGER PIPES FOR LIQUID OF ANOTHER TEMPERATURE, EACH HEAD BLOCK HAVING LARGER BORES RECEIVING THE PIPES OF LARGER DIAMETER AND SMALLER BORES THROUGH WHICH THE PIPES OF SMALLER DIAMETER EXTEND THROUGH AND BEYOND THE HEAD BLOCKS; A TRANSVERSE PASSAGEWAY IN EACH HEAD BLOCK AT ONE END OF THE ASSEMBLED UNITS CONNECTING THE LAYER BORES OF THE HEAD BLOCK AND THE ANNULAR FLOW PASSAGEWAYS OF THE TWO SETS OF PIPES OF THE UNIT WITH EACH OTHER; A TRANSVERSE U-SHAPED CONDUIT AT SAID ONE END OF EACH UNIT CONNECTING THE TWO SMALLER PIPES OF THE UNIT; A DIAGONAL PASSAGEWAY IN EACH HEAD BLOCK AT THE OTHER END OF THE ASSEMBLED UNITS CONNECTING A LAYER BORE OF THE HEAD BLOCK AND THE ANNULAR FLOW PASSAGEWAY OF ONE SET OF PIPES OF THE UNIT WITH DIAGONALLY OPPOSITE LARGER BORE AND THE ANNULAR FLOW PASSAGEWAY OF ONE SET OF PIPES OF AN ADJACENT UNIT; OTHER U-SHAPED CONDUITS AT SAID OTHER END OF THE ASSEMBLED UNITS CONNECTING DIAGONALLY OPPOSITE SMALLER PIPES OF ADJACENT UNITS; AND INLET AND OUTLET MEANS FOR LIQUID OF DIFFERENT TEMPERATURES COMMUNICATIVELY CONNECTED RESPECTIVELY WITH SMALLER PIPES AND WITH ANNULAR FLOW PASSAGEWAYS OF THE HEAD BLOCKS AT SAID OTHER END OF SAID ASSEMBLED UNITS. 